<template>
  <div>
    <!-- 分类参数界面 -->
    <!-- 面包屑导航 -->
    <el-breadcrumb separator-class="el-icon-arrow-right">
      <el-breadcrumb-item :to="{ path: '/home' }">首页</el-breadcrumb-item>
      <el-breadcrumb-item>商品管理</el-breadcrumb-item>
      <el-breadcrumb-item>参数列表</el-breadcrumb-item>
    </el-breadcrumb>
    <!-- 卡片区域 -->
    <el-card>
      <!-- 警告提示模块 -->
      <el-alert title="注意：只允许为第三级分类设置相关参数" type="warning" show-icon :closable="false"></el-alert>
      <!-- 选择商品分类模块 -->
      <el-row class="cat-opt">
        <el-col>
          <span>选择商品分类：</span>
          <!-- 选择商品分类的级联选择框 -->
          <!-- options指定数据源  props用来指定配置对象 
               v-model把数据双向绑定到data中(v-model必须要绑定数组,因为下拉列表可以选择多个分类) -->
          <el-cascader v-model="selectCateKeys" :options="cateList"
                      :props="cateProps" @change="handleChange"
                      clearable>
          </el-cascader>
        </el-col>
      </el-row>
      <!-- tab页签区域 -->
      <el-tabs v-model="activeName" @tab-click="handleTabClick">
        <!-- 添加动态参数面板 -->
        <el-tab-pane label="动态参数" name="many">
          <el-button type="primary" size="mini" :disabled="isBtnDisabled" @click="addDialogVisible=true">添加参数</el-button>
          <!-- 动态参数表格 -->
          <el-table :data="manyTabData" border stripe>
            <!-- 展开行 -->
            <el-table-column type="expand">
              <template slot-scope="scope">
                <el-tag closable v-for="(item, i) in scope.row.attr_vals" :key="i" @close="handleClose(i,scope.row)">
                  {{item}}
                </el-tag>
                <el-input class="input-new-tag" v-if="scope.row.inputVisible"
                          v-model="scope.row.inputValue" size="small" ref="saveTagInput"
                          @keyup.enter.native="handleInputConfirm(scope.row)" @blur="handleInputConfirm(scope.row)">
                </el-input>
                <el-button v-else class="button-new-tag" size="small" @click="showInput(scope.row)">+ New Tag</el-button>
              </template>
            </el-table-column>
            <!-- 索引列 -->
            <el-table-column type="index"></el-table-column>
            <el-table-column label="参数名称" prop="attr_name"></el-table-column>
            <el-table-column label="操作">
              <template slot-scope="scope">
                <el-button type="primary" icon="el-icon-edit" size="mini" @click="showEditDialog(scope.row.attr_id)">修改</el-button>
                <el-button type="warning" icon="el-icon-delete" size="mini" @click="removeParams(scope.row.attr_id)">删除</el-button>
              </template>
            </el-table-column>
          </el-table>
        </el-tab-pane>
        <!-- 添加静态属性面板 -->
        <el-tab-pane label="静态属性" name="only">
          <el-button type="primary" size="mini" :disabled="isBtnDisabled" @click="addDialogVisible=true">添加属性</el-button>
          <!-- 静态属性表格 -->
          <el-table :data="onlyTabData" border stripe>
            <!-- 展开行 -->
            <el-table-column type="expand">
              <template slot-scope="scope">
                <el-tag closable v-for="(item, i) in scope.row.attr_vals" :key="i" @close="handleClose(i,scope.row)">
                  {{item}}
                </el-tag>
                <el-input class="input-new-tag" v-if="scope.row.inputVisible"
                          v-model="scope.row.inputValue" size="small" ref="saveTagInput"
                          @keyup.enter.native="handleInputConfirm(scope.row)" @blur="handleInputConfirm(scope.row)">
                </el-input>
                <el-button v-else class="button-new-tag" size="small" @click="showInput(scope.row)">+ New Tag</el-button>
              </template>
            </el-table-column>
            <!-- 索引列 -->
            <el-table-column type="index"></el-table-column>
            <el-table-column label="属性名称" prop="attr_name"></el-table-column>
            <el-table-column label="操作">
              <template slot-scope="scope">
                <el-button type="primary" icon="el-icon-edit" size="mini" @click="showEditDialog(scope.row.attr_id)">修改</el-button>
                <el-button type="warning" icon="el-icon-delete" size="mini" @click="removeParams(scope.row.attr_id)">删除</el-button>
              </template>
            </el-table-column>
          </el-table>
        </el-tab-pane>
      </el-tabs>
    </el-card>
    <!-- 添加参数/属性对话框 -->
    <el-dialog :title="'添加' + titleText" :visible.sync="addDialogVisible" width="50%" @close="addDialogVisibleClose">
      <!-- 添加参数/属性的表单 -->
      <el-form :model="addForm" :rules="addFormRules" ref="addFormRef" label-width="100px">
        <el-form-item :label="titleText" prop="attr_name">
          <el-input v-model="addForm.attr_name"></el-input>
        </el-form-item>
      </el-form>
      <span slot="footer" class="dialog-footer">
        <el-button @click="addDialogVisible = false">取 消</el-button>
        <el-button type="primary" @click="addParams">确 定</el-button>
      </span>
    </el-dialog>
    <!-- 修改参数对话框 -->
    <el-dialog :title="'修改' + titleText" :visible.sync="editDialogVisible" width="50%" @close="editDialogVisibleClose">
      <!-- 添加参数/属性的表单 -->
      <el-form :model="editForm" :rules="editFormRules" ref="editFormRef" label-width="100px">
        <el-form-item :label="titleText" prop="attr_name">
          <el-input v-model="editForm.attr_name"></el-input>
        </el-form-item>
      </el-form>
      <span slot="footer" class="dialog-footer">
        <el-button @click="editDialogVisible = false">取 消</el-button>
        <el-button type="primary" @click="editParams">确 定</el-button>
      </span>
    </el-dialog>
  </div>
</template>

<script>
  export default {
    name:'Params',
    data() {
      return {
        //商品分类列表(数据源)
        cateList:[],
        //指定级联选择器的配置对象
        cateProps:{
          //指定具体选中那个值的属性
          value:'cat_id',
          //指定看到的属性
          label:'cat_name',
          //指定父子嵌套用的那个属性
          children:'children',
          //次级菜单的展开方式
          expandTrigger: 'hover'
        },
        //级联选择框双向绑定的数组(保存父级分类ID)
        selectCateKeys:[],
        //被激活页签的名称
        activeName:'many',
        //动态参数数据
        manyTabData:[],
        //静态属性数据
        onlyTabData:[],
        //控制对话框的显示与隐藏
        addDialogVisible:false,
        //添加参数的表单/属性对象
        addForm:{
          attr_name:''
        },
        //参数表单的验证规则对象
        addFormRules:{
          attr_name:[{required:true,message:'请输入名称',trigger:blur}]
        },
        //控制修改对话框的控制与隐藏
        editDialogVisible:false,
        //修改参数的表单/属性对象
        editForm:{},
        //修改表单的验证规则
        editFormRules:{
          attr_name:[{required:true,message:'请输入名称',trigger:blur}]
        }
      }
    },
    created() {
      this.getCateList()
    },
    methods: {
      //获取所有的商品分类列表
      async getCateList() {
        const {data} = await this.$http.get('categories')
        if(data.meta.status !== 200) {
          this.$message.error('获取商品分类失败!');
        }
        this.cateList = data.data
        // console.log(this.cateList);
      },
      //级联选择框发生变化触发这个函数
      handleChange() {
        this.getParamsData()
      },
      //tab页签点击事件的处理函数
      handleTabClick() {
        this.getParamsData()
      },
      //获取参数列表数据
      async getParamsData() {
        //证明选中的不是三级分类
        if(this.selectCateKeys.length !== 3) {
          this.selectCateKeys = []
          this.manyTabData = []
          this.onlyTabData = []
          return
        }
        //证明选中的是三级分类
        // console.log(this.selectCateKeys);
        //根据所选分类的ID和当前所处的面板，获取对应的参数
        const {data} = await this.$http.get(`categories/${this.cateId}/attributes`,{params:{sel:this.activeName}})
        if(data.meta.status !== 200) {
          return this.$message.error('获取参数列表失败!')
        }

        data.data.forEach(item => {
          item.attr_vals = item.attr_vals ? item.attr_vals.split(' ') : []
          //控制文本框与按钮的切换
          item.inputVisible = false
          //文本框中输入的内容
          item.inputValue = ''
        });
        // console.log(data.data);

        //通过判断把数据挂载到不同的面板
        if(this.activeName === 'many') {
          this.manyTabData = data.data
        }else{
          this.onlyTabData = data.data
        }
      },
      //监听添加对话框的显示与隐藏
      addDialogVisibleClose() {
        this.$refs.addFormRef.resetFields()
      },
      //点击按钮添加参数
      addParams() {
        this.$refs.addFormRef.validate(async vali => {
          if(!vali) return
          const {data} = await this.$http.post(`categories/${this.cateId}/attributes`,{
            attr_name:this.addForm.attr_name,
            attr_sel:this.activeName
          })
          if(data.meta.status !== 201) {
            this.$message.error('添加参数失败!')
          }
          this.$message.success('添加参数成功!')
          this.addDialogVisible = false
          this.getParamsData()
        })
      },
      //重置修改对话框
      editDialogVisibleClose() {
        this.$refs.editFormRef.resetFields()
      },
      //点击按钮，展示修改对话框
      async showEditDialog(attrId) {
        const {data} = await this.$http.get(`categories/${this.cateId}/attributes/${attrId}`,{params:{attr_sel:this.activeName}})
        if(data.meta.status !== 200) {
          return this.$message.error('修改参数失败!')
        }
        this.editForm = data.data

        this.editDialogVisible = true
      },
      //点击确定按钮，提交修改参数信息
      editParams() {
        this.$refs.editFormRef.validate(async vali => {
          if(!vali) return
          const {data} = await this.$http.put(`categories/${this.cateId}/attributes/${this.editForm.attr_id}`,{
            attr_name:this.editForm.attr_name,
            attr_sel:this.activeName
          })
          if(data.meta.status !== 200) {
            return this.$message.error('修改参数信息失败!')
          }
          this.$message.success('修改参数信息成功!')
          this.getParamsData()
          this.editDialogVisible = false
        })
      },
      //根据ID删除对应的参数项
      async removeParams(attrId) {
        const confirmRes = await this.$confirm('此操作将永久删除该参数, 是否继续?', '提示', {
          confirmButtonText: '确定',
          cancelButtonText: '取消',
          type: 'warning'
        }).catch(err => err)
        //用户取消删除操作
        if(confirmRes !== 'confirm') {
          return this.$message.info('已取消删除操作')
        }
        //删除的操作
        const {data} = await this.$http.delete(`categories/${this.cateId}/attributes/${attrId}`)
        if(data.meta.status !== 200) {
          return this.$message.error('删除参数失败!')
        }
        this.$message.success('删除参数成功!')
        this.getParamsData()
      },
      //文本失去焦点或者按下enter触发
      handleInputConfirm(row) {
        if(row.inputValue.trim().length === 0) {
          row.inputValue = ''
          row.inputVisible = false
          return
        }
        //如果没有return，证明输入的内容需要做后期处理
        //把添加的内容保存到数组中
        row.attr_vals.push(row.inputValue.trim())
        row.inputValue = ''
        row.inputVisible = false
        this.saveAttrValue(row)
      },
      //点击按钮，显示文本输入框
      showInput(row) {
        row.inputVisible = true
        //使文本框自动获得焦点
        //$nextTick方法作用：当页面上元素被重新渲染后，才会指定回调函数中的代码
        this.$nextTick(_ => {
          this.$refs.saveTagInput.$refs.input.focus();
        });
      },
      //删除对应参数的可选项操作
      handleClose(i,row) {
        row.attr_vals.splice(i,1)
        this.saveAttrValue(row)
      },
      //发起请求，保存这次操作到数据库中
      async saveAttrValue(row) {
        const {data} = await this.$http.put(`categories/${this.cateId}/attributes/${row.attr_id}`,{
          attr_name:row.attr_name,
          attr_sel:row.attr_sel,
          attr_vals:row.attr_vals.join(' ')
        })
        if(data.meta.status !== 200) {
          return this.$message.error('修改参数失败!')
        }
        this.$message.success('修改参数成功!')
      }
    },
    computed:{
      // 如果按钮需要被禁用返回true否则返回false
      isBtnDisabled() {
        if(this.selectCateKeys.length !== 3) {
          return  true
        }
        return false
      },
      //当前选中的三级分类ID
      cateId() {
        if(this.selectCateKeys.length === 3) {
          return this.selectCateKeys[2]
        }
        return null
      },
      //计算参数与属性标题的切换
      titleText() {
        if(this.activeName === 'many') {
          return '动态参数'
        }
        return '静态属性'
      }
    }
  }
</script>

<style>
  .cat-opt {
    margin-top: 15px;
  }
  .el-cascader {
    width: 30%;
  }
  .el-tag {
    margin-right: 10px;
  }
  .input-new-tag {
    width: 120px;
  }
</style>